KADE stumbling withOUT fuel pump fuse???

[SINsanity702]

Ive been running rich lately. at least the smog machine is sniffing about 400-800 ppm HC and its high on CO too, but i forget the numbers. anyways, at random times, the car stumbles at idle, and other random times it hesitates to accelerate(as if im not on the gas trying to accel), then itll pick up and go. this happens cold/warm engine, cold/warm weather. however before Spring came around i would start my car around 630am when it would be quite chilly out still(at least for Vegas). and i would have a totally dead #4 cylinder. but im late for work ALWAYS, so i just drove on it....but usually halfway to work it would clear up and run smooth. and the times that it didnt clear up, by the time i leave for lunch and fire it up, its nice and smooth again. but lately i havent had a total missfire in a while and it just stumbles at idle ALOT of the time, its slow to accelerate, and sometimes has that acceleration hesitation as described above. i cleaned the MAFS, i have spark on all 4 cylinders(plugs/wires/cap/rotor are under 10k miles). im assuming i have good fuel pressure cuz im running rich, but i have no pressure tester. so i decided to do a compression test today just to make sure my rebuilt engine is still holding up. i removed the fuel pump fuse to relieve pressure, and started it til it died. Then i cranked it more to get any excess fuel out of the lines..... The engine still tries to come to life though! its not quite running, but its sputtering and will keep sputtering about 1 second after ive stopped cranking(sputters longer if i feather the throttle-about 2 seconds) that means i still have fuel being delivered to the cylinders right? Ive been trying this for about 5 minutes, maybe 10 turnovers with the key and about 25 revolutions of the engine...shouldnt the fuel be gone by now??!! any ideas? maybe the vacuum created by the intake stroke is sucking the fuel from the lines, like an injector stuck open? but isnt there something that stops that?... its a '91 240sx LE 5 spd, with a '93 AT KA24DE engine, and it was rebuilt under 10k miles ago

[sx moneypit]

A fuel pressure gauge would be the easiest way to see if you have a leaking injector.If not pull the fuel rail off ,turn the key on and see if they are leaking.Do this with a cold or cool engine to avoid a chance of fire.
Modified by sx moneypit at 3:49 PM 4/13/2010

[SINsanity702]

well, i just tried it again, and it still stumbles like it has a lil fuel, just not enough....then i unplugged every injector and no stumble, just good healthy spin. then i plugged in 1 at a time, and each one made it want to stumble to come to life, once again, as if it has a bit of fuel, just not enough....ALL this was performed with the fuel pump fuse OUT.....so wtf?! how could fuel be delivered to the injectors(leaking or not) without a pump??

[SINsanity702]

anybody have any input on this?